Since the maximum probability \(s_{ab}\)  of distinguishing two preparations \(P_a\)  and \(P_{b}\)  is at most \(1/2 +\)  \(\Vert  \mu _a - \mu _{b}\Vert /4\) ,
it immediately follows \(s_{ab}\le 1- c_{ab}/2\) , which is the optimal state discrimination probability in noncontextual models, as given in Ref. [1]}. Conversely, it is not immediately obvious how the techniques of Ref. [1]} could be adapted to obtain our result on cloning, due to our use of the data processing inequality in Theorem REF .
